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Concept: Anno Domini

367

How were cities distributed globally in the past? How many people lived in these cities? How did cities influence their local and regional environments? In order to understand the current era of urbanization, we must understand long-term historical urbanization trends and patterns. However, to date there is no comprehensive record of spatially explicit, historic, city-level population data at the global scale. Here, we developed the first spatially explicit dataset of urban settlements from 3700 BC to AD 2000, by digitizing, transcribing, and geocoding historical, archaeological, and census-based urban population data previously published in tabular form by Chandler and Modelski. The dataset creation process also required data cleaning and harmonization procedures to make the data internally consistent. Additionally, we created a reliability ranking for each geocoded location to assess the geographic uncertainty of each data point. The dataset provides the first spatially explicit archive of the location and size of urban populations over the last 6,000 years and can contribute to an improved understanding of contemporary and historical urbanization trends.

Concepts: Statistics, Chronology, Demography, Geographic information system, City, Urban area, Urbanization, Anno Domini

34

An annually resolved and absolutely dated ring-width chronology spanning 4,500 y has been constructed using subfossil, archaeological, and living-tree juniper samples from the northeastern Tibetan Plateau. The chronology represents changing mean annual precipitation and is most reliable after 1500 B.C. Reconstructed precipitation for this period displays a trend toward more moist conditions: the last 10-, 25-, and 50-y periods all appear to be the wettest in at least three and a half millennia. Notable historical dry periods occurred in the 4th century BCE and in the second half of the 15th century CE. The driest individual year reconstructed (since 1500 B.C.) is 1048 B.C., whereas the wettest is 2010. Precipitation variability in this region appears not to be associated with inferred changes in Asian monsoon intensity during recent millennia. The chronology displays a statistical association with the multidecadal and longer-term variability of reconstructed mean Northern Hemisphere temperatures over the last two millennia. This suggests that any further large-scale warming might be associated with even greater moisture supply in this region.

Concepts: Chronology, Precipitation, Climate, Tropical cyclone, Centuries, Monsoon, Global warming, Anno Domini

12

The lowland Maya site of Ceibal, Guatemala, had a long history of occupation, spanning from the Middle Preclassic period through the Terminal Classic (1000 BC to AD 950). The Ceibal-Petexbatun Archaeological Project has been conducting archaeological investigations at this site since 2005 and has obtained 154 radiocarbon dates, which represent the largest collection of radiocarbon assays from a single Maya site. The Bayesian analysis of these dates, combined with a detailed study of ceramics, allowed us to develop a high-precision chronology for Ceibal. Through this chronology, we traced the trajectories of the Preclassic collapse around AD 150-300 and the Classic collapse around AD 800-950, revealing similar patterns in the two cases. Social instability started with the intensification of warfare around 75 BC and AD 735, respectively, followed by the fall of multiple centers across the Maya lowlands around AD 150 and 810. The population of Ceibal persisted for some time in both cases, but the center eventually experienced major decline around AD 300 and 900. Despite these similarities in their diachronic trajectories, the outcomes of these collapses were different, with the former associated with the development of dynasties centered on divine rulership and the latter leading to their downfalls. The Ceibal dynasty emerged during the period of low population after the Preclassic collapse, suggesting that this dynasty was placed under the influence from, or by the direct intervention of, an external power.

Concepts: Time, Maya peoples, Radiocarbon dating, Dynasty, Anno Domini, House of Habsburg, House of Bourbon, Dynasty minor characters

2

Past research on Madagascar indicates that village communities were established about AD 500 by people of both Indonesian and East African heritage. Evidence of earlier visits is scattered and contentious. Recent archaeological excavations in northern Madagascar provide evidence of occupational sites with microlithic stone technologies related to foraging for forest and coastal resources. A forager occupation of one site dates to earlier than 2000 B.C., doubling the length of Madagascar’s known occupational history, and thus the time during which people exploited Madagascar’s environments. We detail stratigraphy, chronology, and artifacts from two rock shelters. Ambohiposa near Iharana (Vohémar) on the northeast coast, yielded a stratified assemblage with small flakes, microblades, and retouched crescentic and trapezoidal tools, probably projectile elements, made on cherts and obsidian, some brought more that 200 km. (14)C dates are contemporary with the earliest villages. No food remains are preserved. Lakaton'i Anja near Antsiranana in the north yielded several stratified assemblages. The latest assemblage is well dated to A.D. 1050-1350, by (14)C and optically stimulated luminescence dating and pottery imported from the Near East and China. Below is a series of stratified assemblages similar to Ambohiposa. (14)C and optically stimulated luminescence dates indicate occupation from at least 2000 B.C. Faunal remains indicate a foraging pattern. Our evidence shows that foragers with a microlithic technology were active in Madagascar long before the arrival of farmers and herders and before many Late Holocene faunal extinctions. The differing effects of historically distinct economies must be identified and understood to reconstruct Holocene histories of human environmental impact.

Concepts: Extinction, History, Foraging, Holocene, Archaeology, Excavation, Anno Domini, Holocene extinction

1

Measuring the impact of online health campaigns is challenging. Ad click-through rates are traditionally used to measure campaign reach, but few Internet users ever click on ads. Alternatively, self-reported exposure to digital ads would be prone to recall bias. Furthermore, there may be latency effects whereby people do not click on ads when exposed but visit the promoted website or conduct campaign-related searches later. Online panels that unobtrusively collect panelists' Web behavior data and link ad exposure to website visits and searches can more reliably assess the impact of digital ad exposure. From March to June 2012, the Centers for Disease Control and Prevention aired the national Tips From Former Smokers (Tips 2012) media campaign designed to encourage current smokers to quit. Advertisements ran across media channels, and the digital ads directed users to the Tips 2012 campaign website.

Concepts: Measurement, Advertising, World Wide Web, Mass media, Blog, Anno Domini, .ad, Click-through rate

0

The aim of this study was to assess the historical trends of metal concentrations in coastal sediments in the vicinity of an inactive mining area, find background values and contamination levels of metals around the Karaburun peninsula, and then search for other sources of mercury in marine sediment cores using multivariate statistical analysis and report the potential ecological risks from that metal contamination. Surface sediment samples were taken from seven stations. Water depths were less than 20 m (coastal area) at stations KB07 and KB08. The depths at stations KB01, KB02, and KB03 were between 20 and 40 m, and stations KB05 and KB06 were more than 40 m (open area). In surface sediments at depths between 20 and 40 m, Mo, Cu, Pb, Zn, Ni, Co, Fe, Cd, Ti, Zr, Sn, As, Y, and Hg levels revealed higher contamination factors (Cf) compared to those of the coastal and open areas. Also, sediment samples were taken for historical records at stations KB01 and KB02 for 2012. Metal concentrations of Cu, Zn, Ni, Co, As, Sb, Cr, Ba, Ti, Al, and Hg in the sediment core samples were significantly higher during the Holocene (~5700 BC to 2000 B.C.) and Medieval Warm periods (~1000 A.D. to 1400 A.D.) and tended to decrease towards the Little Ice Age (2200 B.C. to the birth of Jesus Christ). Background concentration of Hg in sediment was found as 1.67 μg/g around the Karaburun peninsula. Average EF values higher than 20 were identified for As, Hg, Sb, and Ca. Ni and Hg levels were found above the PEL values. It was determined that the accumulation effect of Hg coming from the mafic rocks due to erosion in the marine environment was higher than that of Hg coming from the mine. The factor analyses showed an association between Hg, Ni, and Co. This reveals the importance of the contribution of mafic rocks reaching the marine environment by wave erosion. According to the factor analyses, high concentrations of Pb, Zn, Cd, As, Sb, Ba, Ti, and Zr were detected in the lithogenic sources.

Concepts: Sediment, Factor analysis, Metal, Copper, Erosion, Ice core, Jesus, Anno Domini

0

Advance directives (AD) imply the promise of determining future medical treatment in case of decisional incapacity. However, clinical practice increasingly indicates that standardized ADs often fail to support patients' autonomy. To date, little data are available about the quality and impact of ADs on end-of-life decisions for incapacitated acute stroke patients.

Concepts: Cohort study, Medicine, Clinical trial, Medical ethics, Stroke, Evaluation methods, Romance languages, Anno Domini

0

Advance directives (AD) play a central role in end-of-life treatments, intensive care, and palliative care. However, little is known about the experiences of healthcare professionals with ADs. This study reports on palliative care professionals' views on advance directives (AD).

Concepts: Health care, Palliative care, Learning, Palliative medicine, End-of-life care, Curative care, Nursing specialties, Anno Domini

0

The purposes of the study were to assess awareness and prevalence of advance directives (ADs) among patients with advanced cancer undergoing active outpatient care and to determine factors associated with AD completion before and after the diagnosis of cancer.

Concepts: Anno Domini, .ad

0

Possible changes of cortical excitability after status epilepticus (SE) elicited in 12-day-old rats were studied by means of paired cortical afterdischarges (ADs). Consequences of lithium-pilocarpine status were studied in animals with implanted electrodes 3, 6, 9, 13, and 26 days after SE. Paired low-frequency stimulation with a 1-min interval was repeated after 10 min, and duration of ADs was measured. Control rats received saline instead of pilocarpine; other treatments were the same as in SE group. Postictal refractoriness (i.e., the testing response significantly shorter than the conditioning one) appeared at the age of 18 days in lithium-paraldehyde controls, whereas SE animals exhibited this phenomenon since postnatal day 21. The only significant difference between SE and lithium-paraldehyde controls was found in the second conditioning AD in the oldest group studied-it was longer in 38-day-old SE animals. Our results demonstrated moderate signs of higher excitability of SE rats in comparison with control ones long before appearance of spontaneous seizures.

Concepts: The Age, Epilepsy, Anticonvulsant, Seizure, Status epilepticus, Postnatal, Postictal state, Anno Domini